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I may have just stumbled onto a couple of good 2.5 shortblocks that will soon become frankenmotors. I do have a couple of questions though.

 

Aside from 2.5 head gaskets, is anything else specific to the 2.5 needed, or is it pretty much a straight forward shortblock swap?

 

Also, I have a phase 1 ej22 for my dad's vanaru with the HLA dual port heads; will those heads work on the interference style 2.5 engine, or do I need to swap in SLAs/put on SLA heads from an interference 2.2?

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I may have just stumbled onto a couple of good 2.5 shortblocks that will soon become frankenmotors. I do have a couple of questions though.

 

Aside from 2.5 head gaskets, is anything else specific to the 2.5 needed, or is it pretty much a straight forward shortblock swap?

 

Also, I have a phase 1 ej22 for my dad's vanaru with the HLA dual port heads; will those heads work on the interference style 2.5 engine, or do I need to swap in SLAs/put on SLA heads from an interference 2.2?

 

2.5 head gaskets, and everything else for the 2.2. Intake gaskets, timing belt, etc.

 

You can just bolt the heads right on. It's interference because the piston design, not the head.

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Yep just swap everything from the ej22 onto the ej25 block with ej25 headgaskets and your good to go. I just got done putting one of these into my 91 legacy just over a month ago and i love it. I put delta torque cams on it and i have tons of bottom end power compared to before

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Yep just swap everything from the ej22 onto the ej25 block with ej25 headgaskets and your good to go. I just got done putting one of these into my 91 legacy just over a month ago and i love it. I put delta torque cams on it and i have tons of bottom end power compared to before. Just make sure you run premium with as high of a CR as these engines have or you take a chance blowing up the engine

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My understanding is if you run regular gas the knock sensor will take care of it.

I actually got done putting one of these together at about 11.00 last night...

Junk block with 240k + single port heads.. Just threw together parts I had laying around because my car needed an engine.

 

The car had sat for about 5 months with regular gas in it, and it ran just fine on the test ride.

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Well i know its over a 11:1 CR and anything that high you want to run premium or your taking chances. Im not saying you cant run regular but for longer life of the engine i would run premium so you dont take a chance on getting pre-detonation and blowing a hole in a piston. When your knock sensor helps all its doing is retarding your timing to try and avoid pre-det and you lose power when it has to do that. Just my 2 cents

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But in a pinch I don't think it's going to hurt the engine. Especially if you don't drive with your foot to the floor all the time.

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if you have no other choice and you drive it easy yes you can get away with it but the general rule with that high of a CR or if running a turbo you want to run plus or premium depending on how high of a CR you have. I figure anything over 10:1 run plus, once you start getting towards 11:1 you want premium.

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Ya, but I built mine out of spare bits and pieces because I'm poor. So I can't afford fancy gas.

 

Anyway, back on topic.

Has anyone found evidence that running a step or two colder plugs is better with this motor because it makes more heat?

Just thought about that, wondering if anyone has tried it with any quantifiable results.

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Well I got the pics, and I'm taking the drive to go get the engines tomorrow. 2 complete, albeit disassembled, EJ25? DOHC engines. My dad doesn't want to risk shredding the stock transaxle in his vanagon with anything over 150hp, so I'll be rebuilding one and selling it to recoup costs.

 

I'll be up to 3 1/2 complete EJ engines in my shop... And I had the audacity to question this Subi "addiction". Shame on me.

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